opine vs speak out

opine

verb
  • To give one's formal opinion (on or upon something). 

  • To have or express an opinion; to state as an opinion; to suppose, consider (that). 

noun
  • Any of a class of organic compounds, derived from amino acids, found in some plant tumours 

speak out

verb
  • To assert or promote one's opinion; to make one's thoughts known. 

How often have the words opine and speak out occurred in a corpus of books? (source: Google Ngram Viewer )